He paid 3.19 per gallon both times......first time he bought 12.53 gallons....next time he bought 11.86 gallons
so ur expression is : 3.19(12.53 + 11.86)
<span><span> <span>Akar akar persamaan kuadrat 2x² - 3x -1 = 0 adalah x1 dan x2. Persamaan kuadrat baru yang akar akarnya satu lebih kecil dari dua kali akar akar persamaan kuadrat di atas adalah ........</span></span><span><span><span>A.x² - x - 4 = 0</span><span>B.x² + 5x - 4 = 0</span><span>C.x² - x + 4 = 0</span></span><span><span>D.x² + x + 4 = 0</span><span>E.x² - 5x - 4 = 0</span></span></span><span>Jawaban : A
Penyelesaian :
Akar-akar persamaan lama : x1 dan x2
Akar-akar persamaan baru : xA dan xB
xA = 2x1 - 1
xB = 2x2 - 1
xA + xB = (2x1 - 1) + (2x2 - 1)
= 2 (x1 + x2) - 2
= 2 () - 2
= 3 - 2
xA + xB = 1
xA . xB = (2x1 - 1) (2x2 - 1)
= 4 x1.x2 - 2(x1 + x2) + 1
= 4.(-) - 2() + 1
= -2 - 3 + 1
xA . xB = -4
Jadi persamaan kuadrat baru : x² - (xA + xB)x + xA . xB = 0
x² - x - 4 = 0
</span></span>
Answer:
She will save $5.25
Step-by-step explanation:
21 x 25% = 5.25
Answer:
4m + 5
Step-by-step explanation:
<em>product of 4 and m</em>: 4m
<em>5 more than</em> the product of 4 and m: 4m + 5
Answer: 4m + 5
Answer:
9
Step-by-step explanation:
9.45 is rounded down to 9 because the number must reach half to round up. To round up to 10, it must be 9.5. hope this helps
